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Copper-catalyzed thiophenol C-H activation is described. Through an initial attempt to conduct C-arylation with arylboronic acid, a rather surprising sequential C-H activation and S-arylation was discovered. Mechanistic investigation revealed the disulfide intermediate as the key component in directing C-H oxidation. The overall reaction proceeded under mild conditions with molecular oxygen as the oxidant. Discovery of disulfide as the directing group provides a potential new direction for catalytic C-H functionalization under mild conditions.

Isatin reacts with alkyl and aryl Grignard reagents to form 3-substituted 3-hydroxyoxindoles which are subsequently transformed with various nucleophiles, including allylstannane, thiophenol, indole, acetophenone enol trimethylsilylether and dimethyl malonate.

A simple strategy for the syntheses of 2-alkyl indoles via regioselective ring-opening of 2-(2-haloaryl)-3-alkyl-N-tosylaziridines with thiophenol, followed by copper powder-mediated intramolecular C–N cyclization and subsequent aromatization by the elimination of thiophenol, with good yields is described. Utilizing this protocol, 2-carboxyindole has been synthesized easily.

Here we report a ternary catalyst system for the intramolecular hydroamidation of unactivated olefins using simple N-aryl amide derivatives. Amide activation in these reactions occurs via concerted proton-coupled electron transfer (PCET) mediated by an excited state iridium complex and weak phosphate base to furnish a reactive amidyl radical that readily adds to pendant alkenes. A series of H-atom, electron, and proton transfer events with a thiophenol cocatalyst furnish the product and regenerate the active forms of the photocatalyst and base. Mechanistic studies indicate that the amide substrate can be selectively homolyzed via PCET in the presence of the thiophenol, despite a large difference in bond dissociation free energies between these functional groups.

Three-component reactions of phenylglyoxal monohydrate, phenols, and indoles were developed with the aid of acid-catalyst, which produced various densely substituted benzofurans with good to excellent yields. On the basis of this observation, a one-pot, step-wise reaction was developed by using methyl ketones instead of using phenylglyoxal component in I 2 /DMSO system. At last, three-component reaction offered a useful way to synthesize densely substituted benzofurans starting from simple and easily available substrates. The indole component can be replaced by some other nucleophiles, such as 1,2,4-trimethoxybenzene and thiophenol.

Electrophilic phosphonium cations (EPCs) are efficient main group catalysts for the hydroarylation of olefins under mild conditions, providing a facile route to substituted aniline, bis-arylamine, phenol, furan, thiophene, pyrrole, and indole derivatives. Similarly, EPCs catalyze the hydrothiolation of aryl olefins with thiophenol affording a series of alkyl aryl thioethers. Experimental data support a mechanism for these reactions that involves initial activation of the olefin.

2,3-Dihydro-2,2,2-triphenylphenanthro[9,10-d]-1,3,2-λ5-oxazaphosphole serves as good catalyst for the oxidation of thiophenol, cysteine and glutathione to their disulfides by molecular oxygen. The kinetics of the reactions unveiled an overall second order rate equation for all reactions and pure dioxygen chemistry for all three substrates. The formation of an unstable hydroperoxide from the catalyst is assumed to be a key step during the reaction.

The title compounds are synthesized in water under neutral conditions by the reaction of aromatic aldehydes with 2-amino thiophenol (I) or o-phenylenediamine (IV) mediated by β-cyclodextrin in high yields.

A straightforward synthesis of the silylated tetrahydropyridinyl trifluoromethanesulfonate (VI) is developed and the product is utilized as precursor of N-tosyl-3-azacyclohexene, which is readily trapped by Diels—Alder reaction, 1,3-dipolar cycloaddition, [2 + 2] cycloaddition reaction, thiophenol or Bu3SnH to give products with excellent levels of regioselectivity.

Ring opening reactions of N-protected 2-vinylaziridines (I) and (VIII) with alcohols, amines and thiophenol proceed with excellent regio- and stereoselectivity.

A practical and efficient one-pot synthesis of novel 1,2,3-triazoles featuring nitrogen, oxygen, and sulfur functionalized pendant arms has been developed. The click reaction of mono-propargyl derivatives supported by aniline, thiophenol, and benzyl alcohol, with sodium azide and p-substituted benzyl halogenides, renders a series of N-substituted-1,2,3-triazoles in good yields under mild reaction conditions. The catalyst system was based in Cu(OAc)2 · H2O, sodium L-ascorbate, and 1,10-phenanthroline monohydrate, and all reactions were performed in a mixture H2O–ethanol (4:1 v/v). Additionally, the preparation of bis-1,2,3-triazoles supported by di-propargylated aniline was carried out, demonstrating the versatility of the present methodology. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]

The diastereoselectivity of the nucleophilic epoxidation of 3-hydroxy-2-methylene esters has been studied. The 3-hydroxy-2-methylene esters were obtained through a Morita–Baylis–Hillman reaction. The resulting epoxyesters were treated with thiophenol for transformation into 2,3-dihydroxy-2-((phenylthio)methyl), which upon treatment with triphosgene afforded the corresponding cyclic carbonates.

Notable advantages of the title process are solvent-free conditions, short reaction times, simple operation, high yields, and reusability of the catalyst.

Transition-metal-free chemo- and stereoselective addition of 5-aminoindole (1a), tryptamine (1b), and histamine (1c) to alkynes 2a-s to synthesize the indolyl/imidazolyl enamines 3a-p, 5a-o, and 6a-e using superbasic solutions of alkali-metal hydroxides in DMSO is described. The addition of N-heterocycles onto alkynes takes places chemoselectively without affecting the 1° amino groups (aromatic and aliphatic) of 5-aminoindole, tryptamine, and histamine. The stereochemistry of the products was found to be dependent upon reaction time; an increase in reaction time leads to the formation of a mixture of E/Z isomers and the thermodynamically stable E addition product. The chemoselective addition of N-heterocycle 1a onto alkyne over thiophenol 7 and phenol 8 is supported by control experiments. Competitive experiments showed that 5-aminoindole was more reactive than tryptamine, and histamine was found to be the least reactive. The present methodology provides an efficient chemoselective method to synthesize a variety of (Z)-enamines of 5-aminoindole, tryptamine, and histamine without affecting the 1° amino group. The presence of the free amino group in enamines could be further used for synthetic elaboration, which proved to be highly advantageous for structural and biological activity assessments.

Herein is presented a direct method for the metal-free hydrotrifluoromethylation of alkenes. The method relies on the single electron oxidation of a commercially available sodium trifluoromethanesulfinate salt (CF3SO2Na, Langlois reagent) by N-Me-9-mesityl acridinium as a photoredox catalyst. Methyl thiosalicylate is used as a substoichiometric H-atom donor for aliphatic alkenes, and thiophenol is used as a stoichiometric H-atom donor for styrenyl substrates. The substrate scope for the transformation is broad, including mono-, di- and trisubstituted aliphatic and styrenyl alkenes, with high regioselectivity in nearly all cases examined.

The photochemical reaction of the amine substrates does not require any metal catalyst and is effective in the presence of 9-mesityl-10-methylacridinium tetrafluoroborate and thiophenol as a hydrogen donor.

C–O/C–S cross coupling of aryl halides with phenol or thiophenol was studied under ligand-free condition at room temperature over CuO nanocatalyst. The scope of the reaction was extended to various aryl halides and substituted phenols under optimized condition. In general, efficient, selective, and reusable heterogeneous nano CuO catalytic system has been developed for room temperature C–O and C–S Ullmann type cross coupling reactions.

The samarium diiodide induced cyclization of sulfur-containing precursors to produce thiochroman systems is investigated.

The environmentally-friendly method can be successfully extended to reactions of 2-chloro-5-nitrobenzoic acid with phenol and thiophenol.

The protocol relies on adsorption of the educts to neutral alumina prior to the addition of thiophenol.

A simple method is presented for the stereoselective synthesis of a new family of biologically interesting thiochroman derivatives.

A clean and sustainable transformation of aryl sulfonyl chlorides or sulfonamides into thiophenols is described.

The first synthetic access to tocotrienol thiophenol analogue (VIII) and a convenient route to tocopherol thiophenol analogues (VI) is described.

Both the endo- and exo-isomers of epoxy acetals (II)/(III) are reacted with thiophenol to afford corresponding hydroxy sulfides, which are further transformed in search for new antimycotic substances.

Title ionic liquid-supported TBD efficiently catalyzes the Michael addition of malononitrile (II) as well as thiophenol (IV) towards chalcones (I) under mild conditions (neat, room temperature).

The presence of thiophenol appears to be essential in the synthesis of the indium selenide (III).

Depending on the additive (ZnCl2 or silica gel) and the reaction temperature, different types of addition products can be obtained.

A monoligated Pd-complex is shown to be an excellent precursor for a NHC catalyst to improve the C—S coupling of various aryl halides with thiophenol and benzyl mercaptan.

Polyhaloquinoline-3-carboxylates (I) and (VIII) react with phenols, thiophenols, or anilines highly regioselectively to give mono-, di- or trisubstituted derivatives in dependence on educt ratio and reaction conditions.

The nucleophilic aromatic substitution between electron-deficient aryl halides and phenols, as well as aniline or thiophenol is mediated by clinoptilolite impregnated with KF in DMSO.

Thiophenol, aniline and phenol derivatives are transformed to the corresponding 2-ethynyl-3-iodo-substituted heterocycles which are converted into the title systems.

A highly regio- and enantioselective reaction of allylic carbonates with sodium thiophenolate is realized under conditions A.

Treatment of diones (I) and mixed -Me/-Et analogues affords the target compounds (III)(6 examples) in moderate yields.

Synthesis of isoxazolyl quinoline-3-carboxamides 3 and isoxazolyl-1,4-benzothiazine-2-carboxamides 4 have been accomplished by cyclocondensation of isoxazolyl-3-oxo-butanamides 2 with o-amino benzaldehyde or o-amino thiophenol involving Friedelander's condensation and oxidative cyclization respectively.

Arrhenius rate expressions were determined for the abstraction of hydrogen atom from thiophenol and hexanethiol by the octanethiyl radical at 25-100 {degrees}C in nonane. Octanethiyl radicals were produced by steady-state photolysis of octyl thiobenzoate. Analysis of octyl disulfide and octanethiyl radical. For hexanethiol, log (k{sub abs}/K{sub t}{sup 1/2}) = (2.94 {plus_minus} 0.29) - (3.84 {plus_minus}0.41)/0, and for thiophenol, log (k{sub abs}/k{sub 5}{sup 1/2}) = (2.56 {plus_minus} 0.19) - (2.88 {plus_minus} 0.28)/0;0=2.3RT kcal/mol. Combining these expressions with the Smoluchowski expression for self-termination of octanethiyl in nonane, log (k{sub t}{sup 1/2}) = 5.96 - 1.335/0, which employs experimental diffusion coefficients of octanethiol and a spin selection factor {sigma} = 1, yields, for thiophenol, log (k{sub abs}/M{sup {minus}1}s{sup {minus}1}) = (8.52 {plus_minus} 0.18) = (4.22 {plus_minus} 0.27)/0, and for hexanethiol, log (k{sub abs}/M{sup {minus}1} s{sup {minus}1}) = (8.90 {plus_minus} 0.29) = (5.18 {plus_minus} 0.41)/0 (errors are 2{sigma}). The rate of disappearance of octanethiyl/diphenylketyl radical pairs in SDS micelles, determined by nanosecond optical spectroscopy, was found to be unchanged in a 700-G magnetic field, providing evidence for rapid intersystem crossing of sulfur-centered radical pairs and support for the assignment of {sigma} = 1 above. Ab initio electronic structure calculations on the reaction HS{sup {lg_bullet}}more » + HSH {r_arrow} HSH + {sup {lg_bullet}}SH, performed at SCF and correlated levels, predict an activation barrier of {Delta}H{sub 298} {sup {double_dagger}}= 4.6 kcal/mol, in close agreement with the experimental barrier for the octanethiyl + hexanethiol reactions. 43 refs., 5 figs., 4 tabs.« less

3,4-Diphenyl-5-cyanopyridazin-6-one 3 was prepared from the reaction of cyano-acetamide2 with benzilhydrazone in dry pyridine. A series of its derivatives was prepared. Tolyl and benzene sulphonyl derivatives6a and6b are also prepared. 3,4-Diphenyl-5-cyano-pyridazin-6-thione5 was obtained from3 by the action of P2S5 while 3,4-diphenyl-5-cyano-6-chloropyridazine4 was obtained from3 by the action of POCl3. The reaction of4 with hydrazine hydrate directly afforded the pyrazolopyridazine derivative7. Compound4 also reacted with phenylhydrazine, aniline, thiophenol and anthranilic acid to yield pyridazine derivatives8, 9, 10 and11, respectively. On treatment of compound11 with acetic anhydride it cyclised to afford pyridazino pyrimidine derivatives12.

Thiophenols and diphenylphosphinodithioic acid add to carbonyl-carbon double bound in benzil-monoanil Ia, benzilmonoanil p-toluidine Ib and benzilmonoanil p-chloro Ic to give the corresponding diphenylethyl thiophenol IIIa,d,g, diphenylethyl thiophenol 2-amino III b,e,h and diphenylethyl diphenylphosphinodithioates III o.f.I respectively. The given structures were based upon analytical. chemical and spectroscopic results.

Condensation between glyoxal thiophenol and N-substituted ( R )-phenylglycinol led to morpholine derivatives. The totally stereoselective formation of heterocycle 6 gives access to a chiral masked form of glyoxal in which the symmetry features of the dialdehyde have disappeared. The cyclisation is consistent with Baldwin rules for ring closures when applied to different competing pathways. AMI conformational calculations were used in order to rationalize the stereochemical outcome of the reported transformation.

The pyrolyses of p-nitrophenyl t-butyl ether, p-methoxyphenyl t-butyl ether, p-aminophenyl t-butyl ether, p-nitrophenyl t-butyl sulfide, and propargyl t-butyl sulfide have been studied in a stirred-flow reactor over the temperature range 430-530 o C and pressures in the range 7-14 torr, using toluene as carrier gas. The reactions yielded between 90 to 99% isobutene plus the corresponding phenol, thiophenol, or thiol as products. The first order rate coefficients for reactant consumption, based on isobutene production, followed the Arrhenius equation p-nitrophenyl t-butyl ether k(s −1 )=10 12.79±0.24 exp(−179±3 kJ/mol RT) p-methoxyphenyl t-butyl ether k(s −1 )=10 14.50±0.30 exp(−210±4 kJ/mol RT) p-aminophenyl t-butyl ether k(s −1 )=10 14.59±0.28 exp(−208±4 kJ/mol RT) p-nitrophenyl t-butyl sulfide k(s −1 )=10 12.12±0.27 exp(−185±4 kJ/mol RT) propargyl t-butyl sulphide: k(s −1 )=10 13.79±0.24 exp(−204±3 kJ/mol RT). The results support a unimolecular elimination of the isobutene involving polar, four-center cyclic transition states

γ,δ-Unsaturated ketones were found to be oxygenated in the presence of thiophenol to give the corresponding cyclic peroxides. The electrochemical initiation accelerated the reaction markedly.

The synthesis of quinic acid (4) via epoxide 13, starting from shikimic acid (5), is described (Scheme 1). Treatment of 13 with thiophenol yielded not only 17, but also the γ-lactones 18 and 19 as result of migration of silyl groups within a cis- and trans-diol system. The conversion provides a direct stereoselective epoxidation of a shikimic-acid derivative as well as an alternative pathway for the preparation of 4. A shorter approach via the disilylated epoxide 22 was unsuccessful because the γ-lactone 25 was obtained in place of the desired α-hydroxy ester 24 (Scheme 2).

A series of dienylamides have been found to undergo radical cyclisation when irradiated in the presence of diphenyl disulfide and thiophenol. The present method provides an attractive entry to the preparation of lactams from easily available dienylamides.

Distereoface differentiating nucleophilic of thiophenol to olefins delivers a new concomitant asymmetric construction of two contiguous stereogenic centers and has been successfully applied to the asymmetric synthesis of (+)-diltiazem.

Summary The possibilities offered by magnetic techniques to better understand metal catalyst deactivation are illustrated by four examples from the literature and from unpublished data: i) magnetic measurements which are performed in situ under the working pressure of up to 50 bars yield with a good accuracy the evolution of particle size of Ni-based catalysts and Co–Cu/Al 2 O 3 catalysts in the course of the methanation reaction and of the synthesis of C 2+ alcohols from syngas, respectively, ii) magnetic methods shed some light on the interaction of carbon deposits with Ni and on their identification, iii) the variation of saturation magnetization of Ni with the quantity of adsorbed poisons gives information on the number of Ni atoms involved in the bonding. Magnetic isotherms show also that the adsorption of some gases is corrosive in the sense that bulk together with surface Ni atoms are involved in chemical bonding while the adsorption of molecules such as thiophenol leaves free Ni surface atoms; iv) magnetism gives evidence of the long range interaction of some poisons such as As in (on) Ni.

The reaction between a chiral template derived from glyoxal with organometallic reagents leads ultimately to the optically active title compounds. The stereochemical outcome of the key-step which involves substitution of a thiophenol group depends on the organometallic: predominantly inversion with alkyl copper or complete retention with alkyl zinc halides. The stereodirecting effect of an allylic hydroxy group in an iminium intermediate is evidenced in the case of the organozinc reagent.

(1R*,6S*,8R*)-8-Methylsulfonyl-2-oxa-7-thiabicyclo[4.2.0]octane 7,7-dioxide 10a, available from the reaction of 3,4-dihydro-2H-pyran and methylsulfonylsulfene 1(generated in situ from MeSO2Cl and Et3N), underwent alkylation at position 8 in the presence of sodium hydride and alkyl halides. With methyl iodide and chloromethyl methyl ether, mixtures of the endo- and exo-methyl derivatives 10b and 11b(with 10b in predominance) and the endo- and exo-methoxymethyl derivatives 10c and 11c(with 11c in predominance) were produced. With benzyl chloride, tert-butyl bromoacetate and allyl bromide, only the exo-alkyl derivatives 11d-f were isolated, the stereostructure of compound 11f being established by X-ray crystallography.In the presence of sodium thiophenoxide and thiophenol, compound 10a underwent a reductive cleavage of its S(7)–C(8) bond to give, after acidification, the sulfinic acid 9a; the sodium salt of the last-cited acid underwent methylation with methyl iodide to give (2S*,3S*)-3-methylsulfonyl-2-(methylsulfonylmethyl)tetrahydropyran 15d. Under corresponding conditions (and also in the presence of a large excess of Na/Hg in MeOH), compound 11f afforded the sulfinic acid 27c which was transformed into (2R*,3S*)-3-methylsulfonyl-2-[(1′R*)-1′-(methylsulfonyl)but-3′-enyl]-tetrahydropyran 21d; the stereostructure of the last cited compound was determined by X-ray crystallography. The sulfinic acid 27c also underwent reaction with diazomethane to give the methyl sulfinate 27b as a ∼ 1 : 1 mixture of diastereoisomers.In the presence of Raney nickel, compound 10a furnished (2R*)-2-(methylsulfonylmethyl)-tetrahydrofuran 14 whereas compound 11f underwent reduction of its olefinic linkage to give the propyl derivative 11h.Sodium methoxide in methanol (and also Na/Hg in MeOH) induced an overall hydrolytic cleavage of the S(7)–C(8) bonds of compounds 10a and 11f to give, after acidification, the cis-sulfonic acids 15c and 21b(which were isolated as their methyl esters 15a and 21a). In the presence of sodium hydroxide, the cis-sulfonic acid 15c underwent epimerisation at position 2 to give the trans-sulfonic acid 17c(which was isolated as its methyl ester 17a).

The preparation of ortho-substituted O-aryl and O-pyrid-3-yl thiocarbamates 7a-h and 11a-d and anionic ortho-Fries rearrangements of selected cases, [O-phenyl N,N-diethylthiocarbamate (6a)→N,N-diethyl-2-hydroxy-3-methylbenzenecarbothioamide (9), 0-[4-(trimethylsilyl)pyridyl-3-yl] N,N-diethylthiocarbamate (11a)→N,N-diethyl-3-hydroxy-4-(trimethylsilyl)pyridine-3-carbothioamide (13)], via the directed ortho metalation protocol are described